Many efforts have been made over the years to make the drudgery of cleaning bathrooms, and toilets in particular, less of an unpleasant chore. Whereas toilet cleaning generally required the rigorous scrubbing of the bowl with a brush and an abrasive powdered bleach or detergent, automatic toilet bowl cleaners have been around now for a number of years and require little more effort than the customary flush that one conducts after each use. These cleaners generally consist of a liquid, a solid tablet or a granular material that is dropped in the cistern or tank which sits atop the bowl. Liquid and granular formulations are generally provided in plastic dispensing containers or bottles whereas the solid formulations may just consist of the solid tablet itself. The cleanser/sanitizer slowly dissolves in the water of the tank and with each flush is released to the bowl where it swirls about, cleansing and disinfecting the anionic porcelain surface.
Solid lavatory or urinal cleansing compositions are commonly utilized today to clean, deodorize and disinfect toilet water and toilet fixtures. These compositions are typically shaped in the form of "blocks" or "cakes" and are placed by the user in the toilet tank or bowl, or in urinals. The blocks are then designed to slowly dissolve and thereby release part of their active composition over time. It is this time-released attribute which many have found to be invaluable in dispensing functional agents to the water. In many instances, the action of flushing also serves to further dispense the active ingredients.
Liquid toilet bowl cleaners on the other hand must be applied manually and are generally comprised of gel or viscous liquid that is squirted from a squeezable container or bottle about the upper rim of the toilet bowl. Some formulations are left to slowly coat the bowl surface through gravitational pull and clean over several hours or, in most cases, a brush is used to manually scrub the surface and the dirt, grime and soap scum is then flushed away.
There are many different formulations known in the art with respect to both types but all generally comprise a water soluble surfactant, a halogen releasing agent, binders, dyes, fillers and perfumes.
Surfactants, more generically known as soaps or detergents, are surface active agents that clean soiled or stained surfaces by lowering the surface tension or surface energy that binds two materials, in this case two solids, together. Surfactants concentrate at the solid-solid or solid-liquid interface between two materials and reduce the surface tension at this point thereby separating the two which cleans the surface.
Many toilet bowl cleansers employ a variety of halogen-containing materials that are known to serve as disinfecting and/or sanitizing agents. These materials are believed to function as disinfecting agents by virtue of the formation of a hypohalite ion, e.g., hypochlorite ion, or hypohalous acid, e.g., hypochlorous acid, when the material is dissolved in a aqueous medium. Typically, the halogen-containing material is a chlorine, bromine, iodine or chlorine and bromine-containing material. Representative examples of such halogen-containing materials include: the hypochlorites, such as lithium hypochlorite and calcium hypochlorite, chlorinated isocyanuric acids, such as dichloroisocyanuric acid and its sodium and potassium salts, trichloroisocyanuric acid, the chlorinated and brominated hydantoins, such as 1,3-dibromo-5,5-dimethylhydantoin, the N-halo-2-oxazolidinones, such as 3-chloro-4,4-dimethyl-2-oxazolidinone, and N,N-dihalo-2-imidazolidinones, such as 1,3-dichloro-4,4,5,5-tetramethyl-2 imidazolidinone.
The dye or coloring agent imparts a colored hue to the otherwise clear toilet bowl water and this serves two purposes. On the one hand, the dye adds a certain aesthetic value in that the blues and greens of the dyes known in the art are pleasing to the eye. More importantly, the dye serves as an indicator function in that it's absence, when depleted, also indicates the depletion of the cleanser/disinfectant and serves notice that the depleted cleanser/disinfectant is no longer present or active.
A problem inherent with many of the halogen disinfectants, surfactants and dyes is their relatively caustic nature which is a necessary attribute for the cleaning of these plumbing fixtures. The surfaces of most toilet bowls on the other hand, is generally comprised of porcelain which is susceptible to attack by the ions formed by these compounds when dissolved in water. The toilet bowl surfaces are generally anionic by nature while many of the halogens, surfactants and dyes form cations when released in solution. These cations, as well as naturally occurring minerals found in the systems water will often bond to and stain the anionic porcelain surface. Orange iron spots are commonly seen as a result of high iron levels in the water supply. If left untreated, these can become quite unseemly and are difficult to remove at best.
One solution to removing and preventing the appearance of these stains would be to incorporate a water insoluble component in the cleanser/disinfectant composition that would somehow be attracted to or adhere to the anionic surface of the toilet bowl so as to form a protective coating. U.S. Pat. No. 4,145,303 to Loudas for example, discloses a fluorochemical detergent composition for the cleaning of carpets, upholstery, leather and the like which also imparts a water, oil and stain repellant thereto. A composition that could provide the same functions in a toilet bowl cleanser would likewise have substantial utility.
U.S. Pat. No. 3,754,941 to Burke discloses compositions useful in the cleaning and removal of metallic stains from a porcelain toilet bowl. The compositions are comprised of a metallic salt oxidant such as mercuric chloride coupled with a fluoride solubilizer and a halide activator. The fluoride solubilizer is a surfactant which assists the metallic oxidant with the removal of stains from the porcelain surface by altering the adherence force of the stain to the surface. The halide promoter is selected from the group comprising chloride, bromide and iodide and these activate the metallic salt oxidant whereby stain removal is increased.
It is an object of the present invention to provide a sustained release, continual dispersion of a toilet bowl cleanser which not only cleans but protects toilet bowl surfaces as well. The present invention achieves this goal through the use of a fluorosurfactant coating agent, an anionic or nonionic cleaner, a rheology control agent and aesthetically enhancing excipients. As the cleaning agents remove mineral deposits, surface stains, dirt, grime and the like from the porcelain surface, the fluoro-surfactant adheres to and coats the surface continually preventing or inhibiting further stain and deposit formation.